This invention concerns a quick mounting device with a centering effect for mounting a motor vehicle wheel on the axle of a balancing machine.
German Patent De 3,808,755 C2 discloses a quick mounting device of the type in question. With this type of mounting device a flange for frictional engagement of the rim of a motor vehicle wheel is mounted permanently on the axle. Chucking devices are used to tighten the rim against the flange. In addition, a conical arrangement is also provided for engaging in the central hole of the rim. A spring presses the conical arrangement in the direction of the centering hole. The conical arrangement has an outer part with a cylindrical outside face for engagement in the centering hole of the motor vehicle wheel and with a conical inside face. In addition, the conical arrangement has an inside part having an internal bore for placing the inside part on the axle of the balancing machine, and it has a conical outside face shaped so it is complementary to the conical inside face of the outside part and rests against it. The two parts of the conical arrangement can be spread apart radially. A radial flange with a contact face for coming in contact with the rim of the motor vehicle wheel is provided on the outside part. The inside part of the conical arrangement is placed under a bias tension by a spring acting in the direction against the direction of tightening of the motor vehicle wheel.
The inside part and the outside part of the conical arrangement are partially slotted in the axial direction so that they can be spread apart radially in this area.
When a motor vehicle wheel is placed on the outside part of the conical arrangement, the rim rests against the radial flange on the outside part so it is entrained against the tension direction of the spring in contact with the inside part of the conical arrangement.
The bias tension provided by the spring results in a force which causes the spreadable area of the outside part of the conical arrangement on the conical outside face of the inside part to be divided and thus spread apart outwardly so the cylindrical outside surface is in contact with the inside edge of a centering hole of the rim. The radial spreading results in a tolerance-free centering of the centering hole and thus the rim with respect to the axle of the balancing machine.
One disadvantage of this know quick mounting device is that the radial spreadability is relatively minor because the outside part can be spread apart radially only to a limited extent since it forms a partially slotted sleeve. Above the unslotted portion of the sleeve, the spreadable parts are interconnected so the spreadability is very limited in accordance with the low radial elasticity. Therefore, practically, it is necessary to provide a separate conical arrangement for each centering hole diameter. This requires a great expense for the user.
An object of this invention is to provide a quick mounting device of the type in question that is suitable for different centering hole diameter.
A feature of this invention is to design the spreadable elements of the outside part of the conical arrangement as segments that are completely independent of each other and thus can move unhindered over a wide radial range practically parallel to each other without resulting in jamming, twisting or excessive ending. A basic idea of this invention is to design the spreadable elements of the outside part of the conical arrangement as segments that are completely independent of each other and thus can move practically in parallel over a large radial range with no hindrance and without jamming, twisting or bending excessively. The loose segments are held on the inside parts only by the resilient devices.
The resilient devices may be formed by an elastic ring that surrounds the segments with some tension. The elastic ring may preferably run in a circumferential groove in the segments.
Another expedient refinement of this invention consists of the fact that the segments are secured by guides to prevent them from moving in the circumferential direction. This is advantageous because in this way their arrangement in the circumferential direction cannot change, which would have negative effects on the accuracy of the balancing operation. The guides may be formed by pins which project outward out of the segments and are guided in axial slits in the inside part of the conical arrangement.
Finally, an expedient refinement of the present invention consists of the fact that the segments have edges that face radially inward and engage behind mating edges on the inside part of the conical arrangement and thus prevent axial slippage of the segments down from the inside part.